HPE FlexNetwork 5510 HI Series Network Management And Monitoring Configuration Manual page 92

•
Log—Logs event information (including event time and description) in the event log table so the
management device can get the logs through SNMP.
•
Trap—Sends an SNMP notification when the event occurs.
•
Log-Trap—Logs event information in the event log table and sends an SNMP notification when
the event occurs.
•
None—Takes no actions.
Alarm group
The RMON alarm group monitors alarm variables, such as the count of incoming packets
(etherStatsPkts) on an interface. After you create an alarm entry, the RMON agent samples the
value of the monitored alarm variable regularly. If the value of the monitored variable is greater than
or equal to the rising threshold, a rising alarm event is triggered. If the value of the monitored variable
is smaller than or equal to the falling threshold, a falling alarm event is triggered. The event group
defines the action to take on the alarm event.
If an alarm entry crosses a threshold multiple times in succession, the RMON agent generates an
alarm event only for the first crossing. For example, if the value of a sampled alarm variable crosses
the rising threshold multiple times before it crosses the falling threshold, only the first crossing
triggers a rising alarm event, as shown in
Figure 30 Rising and falling alarm events
Private alarm group
The private alarm group enables you to perform basic math operations on multiple variables, and
compare the calculation result with the rising and falling thresholds.
The RMON agent samples variables and takes an alarm action based on a private alarm entry as
follows:
1. Samples the private alarm variables in the user-defined formula.
2. Processes the sampled values with the formula.
3. Compares the calculation result with the predefined thresholds, and then takes one of the
following actions:
Triggers the event associated with the rising alarm event if the result is equal to or greater

than the rising threshold.
Triggers the event associated with the falling alarm event if the result is equal to or less than

the falling threshold.
If a private alarm entry crosses a threshold multiple times in succession, the RMON agent generates
an alarm event only for the first crossing. For example, if the value of a sampled alarm variable
Figure 30.
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